LightSquared Pulls the Plug

Philip Falcone, the hedge-fund manager who staked his fortune and reputation on an all-in bet on wireless telecommunications, may be losing his grip on both.

Mr. Falcone's LightSquared Inc., a wireless-networking venture, filed for Chapter 11 bankruptcy protection Monday. The move, which came after the company failed to reach an agreement with its lenders to avoid a default, further clouds the future for Mr. Falcone and his...